import os
from contextlib import asynccontextmanager
from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from fastapi.staticfiles import StaticFiles

from app.core.database import SessionLocal
from app.services.seed import seed_initial_data
from app.services.scheduler.watchdog import start_watchdog, stop_watchdog
from app.api.v1.router import api_router


@asynccontextmanager
async def lifespan(app: FastAPI):
    # Startup
    db = SessionLocal()
    try:
        seed_initial_data(db)
    finally:
        db.close()
    start_watchdog()
    yield
    # Shutdown
    stop_watchdog()


app = FastAPI(
    title="Virtual MIS API",
    version="2.0.0",
    description="SaaS 虛擬 MIS 平台管理後端",
    lifespan=lifespan,
)

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

app.include_router(api_router, prefix="/api/v1")


@app.get("/health")
def health():
    return {"status": "ok", "service": "vmis-backend"}


# 靜態前端（admin portal）— 掛載在最後，讓 API 路由優先
_frontend_dir = os.path.join(os.path.dirname(__file__), "..", "frontend")
if os.path.isdir(_frontend_dir):
    app.mount("/", StaticFiles(directory=_frontend_dir, html=True), name="frontend")